docs: def bounding_box(img):
      r"""
      Return the bounding box incorporating all non-zero values in the image.
      
      Parameters
      ----------
      img : array_like
          An array containing non-zero objects.
          
      Returns
      -------
      bbox : a list of slicer objects defining the bounding box
      """
      locations = numpy.argwhere(img)
      mins = locations.min(0)
      maxs = locations.max(0) + 1
      return [slice(x, y) for x, y in zip(mins, maxs)]